Fuel injection mechanism



Sept. 14, 1948.

L. E. JOHNSON v 2,449,120

FUEL INJECTION MECHANISM Filed Aug. 25, 1943 3 Sheets-Sheet 2 INVENTOR. Lloyd 5'. Johnsan KM /W* p 1948. 1.. E. JOHNSON 2,449,120

' m1. mmcnou unczumrsu Filed Aug. 25, 194-3 3 Sheets-Shoot 3 V INVENTOR. Lloyd E. Johnson Patented Sept. 14, 1948 roar. mmo'rrou mzcnamsm Lloyd E. Johnson, Fon du Lac Township, Talewell County, Ill., assignor to Caterpillar Tractor 00., San Lcandro, Calif., a corporation of California I Application August 25, 1943, Serial No. 499,891

1;: Claims. (or 1024-41) 1 My invention relates to fuel injection mechanism, and more particularly to fuel injection pump mechanism having a pump plunger of the type wherein metering of fuel is controlled by angular adjustment of the plunger.

In such type of mechanism, it is desirable that the parts he so arranged that they may be easily and quickly assembled or disassembled My invention has as its objects, among others. the provision of improved fuel injection mechanism oi the character described having an improved arrangement of parts enablin angular adjustment of the pump plunger, and which is of relatively simple. compact and reliableconstruction, and easy to assemble; which includes a pump casing that may be detachably connected as a unit to a pump control casing and which has improved mechanism for positioning controllable parts in the pump casing so that they may be easily connected to parts in the control casing in proper timed relationship therewith; which embodies improved tappet mechanism of a relatively simple construction for actuating the pump plunger; and which also contains improved means for bleeding air. Other objects of my invention will become apparent from a perusal of the following description thereof.

Referring to the drawings:

Fig. l is a fragmentary developed vertical sectional view of the fuel injection mechanism of my invention; the planes of the section being indicated by lines 1-! inFig.2.

Fig. 2 is an elevational view looking in the direction of arrow 2 in Fig. 1.

Fig. 3 is a section taken in planes indicated by line 3-3 in Fig. 1.

Fig. 4 is a sectional elevation taken in planes indicated by line 4-4 in Fig. 1.

' Fig. 5 is a fragmentary section taken in a plane indicated by line I! in Fig. 3.

Fig. 6 is a fragmentary section taken in a plane indicated by line i-B in Fig. 3.

therefor which contains governor controlled rack bar 4 forslmultaneously angularly adjusting all the pump plungers in accordance with engine demands. Should the engine be a radial engine, control casing -3 will generally be ringlike in shape; and a plurality of fuel injection pump casings 2 will be peripherally or clrcumferentially disposed about the control "casing. Also, instead of member 4 being a straight rack, it may be in the form of a ring gear. Reference is made to my assignees copending application by Lloyd E. Johnson and Carl R. Waxwell, filed August 25, 1943, under Serial No. 499,892, new Patent'No. 2,398,182, April 9, 1946, which discloses an arrangement'for a radial compression ignition or Diesel engine; it being understood that such arrangement is equally applicable for radial spark ignition engines having solid fuel injection mechanisms.

Adjacent the fuel discharge end thereof, pump casing 2 is formed with an internal shoulder I valve 9; such clamping being through a remov- Fig. 7 is a fragmentary section taken in a plane indicated by line 1-1 in Fig. 4.

Fig. 8 is a fragmentary section taken in a plane indicated by line 8 -8 in Fig. 1.

The fuel injection mechanism of my invention comprises housing means including a pump casing 3 detachably mounted on a control, or a tappet and camshaft casing I, only a portion of the latter being shown in Fig. 1. In this connection, it is to be understood that in a multiple cylinder. in line engine, a plurality of pump casings, one for each cylinder of the. engine, are

generally mounted on a single control casing ably mounted plunger barrelor cylinder ll having an enlarged head portion 12 clamped against cage 8. by means of a nut I! screwed in the inside of pump casing 2 against shoulder l4 on head It;

a suitable sealing ring it being interposed between nut l3 and shoulder l4. Thus, nut it about cylinder ll removably clamps cage I and cylinder ll between it and internal shoulder I, by applying pressure against head 12 of the cylinder. The flat end surface l5 of head I2 serves as a seat for check valve 9 and thus no separate check seat part is required. This makes for a relatively simple, compact arrangement, wherein the means for removable mounting of the described parts is located inside the pump casing.

To facilitate screwing and unscrewing of nut it when this is desired, it is preferably formed with inwardly extending slots 'll to enable it to be engaged by a suitable tool. A cap screw ll screwed in casing 2, is provided with an end extension ll engaging in a recess 2| formed in head 12 of cylinder I l, for the purpose of holding such cylinder against angular or turning movement when it is clamped in position. Opposite cap screw it, cylinder H is provided with a port or orifice 22 for preferably of the type wherein the quantity of fuel fed or injected past check valve 9, is controlled by angular adjustment or rotation of the plunger about its axis. For this purpose, plunger 24 is formed adjacent its discharge or injection end 25 with an annular groove 26 around its periphery, which communicates with an axially extending groove 21 adjacent a slanting or scroll edge 26 adapted to work past port 22 as the plunger is reciprocated and angularly adjusted.

Fuel discharge end 25 of the plunger is flat, and at a right angle to the axis-oi the plunger. Thus, as the plunger is reciprocated by suitable actuating means and angularly adjusted by suitable governor means, metering of fuel injected by the pump is controlled in a well-known manner. When pump plunger 24 is actuated on its compression stroke to inject fuel during the time port 22 is closed as the plunger works therepast, the pressure imparted to the fuel may be as high as two thousand to four thousand (2,000 to 4,000) pounds per square inch.

Guide means is provided to prevent application of lateral forces on the plunger '24 as it is reciprocated, in association with tappet mechanism for moving the plunger axially in one direction to provide the injection stroke therefor, and spring means for moving the plunger in an opposite direction to provide the suction or return stroke. The guide and spring return means includes a cup-shaped sleeve member 3| slidably mounted in pump casing 2, and having a transversely extending wall 32 provided with a flat portion 33 on its outer surface adapted to engage tappet mechanism 34 removably mountedin control casing 3. To preclude turning of sleeve 3|, it is provided with an elongated slot 34 in which an extension 35 on a cap screw 35 engages, as can be seen from Figs. 3 and 5. Tappet mechanism 34, which will be subsequently described in greater detail, has a fiat portion 36 on the end of an adjustable screw 31, engaging flat portion 33 on sleeve wall 32.

The tappet end portion of plunger 24 extends beyond the tappet end of cylinder ii, and into guide sleeve 3|; such tappet end of the plunger having a flat surface 36 adapted to engage freely a fiat surface 39 on the inner surface of sleeve wall 32. Thus, wall 32 is located between the tappet mechanism 34 and the tappet end of the plunger; and as the plunger is moved axially by tappet mechanism 34, it may be readily turned angularly for the purpose previously explained. A spring 4| is provided about cylinder Ii, and is compressed or interposed between an internal shoulder 42 in pump casing 2, forming an abutment for one end of the spring, and a spring retainer 43 at the tappet end portion of the plunger.

Spring retainer 43 is formed with an inwardly extending slot44 to enable it to be slipped over plunger 24, and is adapted to be thrust against a shoulder or peripheral flange 46 formed on the plunger at a location spaced from sleeve wall 32; the spring retainer 43 having a centrally disposed boss 41 for centering the spring. Also, spring retainer is adapted to be thrust by the spring against an end 48 of sleeve 3|. When spring 4| thrusts retainer 43 against sleeve end 48 on the return stroke of the plunger, the spacing between the surface on shoulder 46 adapted to engage retainer 43, and the fiat surface 36 at the tappet end of the plunger, is such as to provide a slight clearance for the plunger parts between sleeve wall 32 and retainer 43, thus en- 4 abling plunger 24 to be angularly adjusted with ease. Also this clearance prevents the transmission of any lateral forces, which might be produced by an imperfect spring 4|, to the tappet end or the plunger. It is to be noted that-spring 4| is at one side of the retainer 43, andsleeve 3| at the opposite side. This makes for a simple arrangement, which is easy to assemble, and

readily accessible for replacement or repair.

Tappet mechanism 34- may be of any suitable construction but is preferably 01' the type disclosed, which comprises a sleeve 5| having a peripheral shoulder 62 seated in a recess formed in the pump side of control casing .3; the sleeve being held against turning, by a cap screw 53 interlocked with shoulder 52, as is seen more clearly in Figs. 4 and 7. Slidably mounted in sleeve 5| is a crosshead member 54 having fixedly secured therein by pressing, a pin 56 on which is journalled a roller 51 adapted to engage suitable cam mechanism (not shown) in control casing 3 for actuating the tappet mechanism. Above cam engageable roller 51, tappet mechanism 34 has secured thereto by any suitable means, such as welding, a plate 58 in which is screwed the previously mentioned tappet screw 31 which is locked in position by a lock nut '56.

Sleeve 5| is provided with diametrically opposite apertures 6| which, when crosshead 54 is positioned therein during assembly of the tappet mechanism, permit ready insertion of pin 56 into crosshead 54. Also. provided in sleeve 5|, is an elongated slot 62 communicating with one of apertures 6|, and in which a flat end 63 on .pin 56 engages to preclude turning of the crosshead relative to the sleeve, as it is reciprocated in the sleeve.

Means in the pump casing 2, enabling angular adjustment of the pump plunger while it is axially reciprocated, includes a tooth member or gear sector secured to plunger 24 within sleeve 3|, and which has its teeth 12 accessible through an opening I3 formed in the periphery of sleeve 3|. Gear sector H is split at I4, and is rigidly clamped to the tappet end portion of plunger 24 bet-ween shoulder 46 and sleeve wall 32, by a cap screw 16. Sector 'II meshes with another gear member which is journalled in a lateral extension 16 on pump casing 2 about a pin 16 pressed into a wall of extension 16 and which, for added security, is held by a spring retainer 6| at one end thereof; the pin having at its op posite end, a shoulder or flange 62 on which gear 1 member I1 is supported. With referenrce to Fig.

1, it is to be noted that one side 63 of the gear member 11 and the shoulder 62 are spaced from the plane of contact of pump casing 2 with control casing 3; while hub 64 on gear I1 enables spacing of the opposite side' 66 of gear TI from wall 6|) of easing extension 16/ Because of meshing engagement between gear members Ii and TI, turning of gear member ll will resultin turning of gear member H, with consequent angular adjustment of pump plunger 24. Governor controlled means is provided in pump control casing 3 for moving or turning gearing II and H, and which is detachabiy connecta'bie to such gearing, when pump casing 2 is mounted on control casing 3; cap screws 61 detachably connecting such casings.

Supported in control casing 3 is a sleeve 6| in which is journalled a turnable rod 92 having ad jacentits inner end a gear 33 meshing with rack or ring gear 4. Suitable bearing bushings 94 (only one of whisch is shown in Fig. l) are provided between sleeve 3| and rod 32. The outer end of rod 02 extends beyond the surface of control casing 3 adapted to contact pump casing 2, and into thespace formed between gear side -33 and such surface. To such projecting end of rod 02 is adiustably secured a coupling member 33 turnable with rod 32; coupling member 30 being split at 31 and being clamped in adjusted position on rod 32 by ICED screw 90. In its periphery, coupling member 03 is provided with wing extensions I00, for a purpose which will be subsequently described, and a recess'or opening 30 in which a pin IN on gear member 11 is adapted to engage. Thus, a simple pin-type coupling is provided between the gearing in pump casing 2 and the turnable means in control casing 3. v

The control means in control casing 3, being gearing 1I and 11 to assume a predetermined position.

With particular reference to Fig. 3, it will be noted that gear member 11 is provided with a peripheral notch I03 of predetermined length; the notch formed spaced abutments I04 which are adapted to engage a removably mounted stop pin I01 formed as a, cap screw secured in pump casing 2. Stop pin I01 and abutments I04 provide stop means which limits the degree of turning of plunger 24, to insure that when the pump is disconnected, plunger 24 will not turn one hun dred and eighty degrees (180) out of phase. Also, when pump casing 2 is detached and consequently the pump is idle, pin I01 can be engaged by one of abutments I04 at a predetermined fixed position which is such that when the pump casing 2 is to be connected to control casing 3, coupling pin IOI will be in line with opening 99, thus enabling the quick detachable connection with proper tlmingof the pump, between pump casing 2 and control casing 3. In assembling or disassembling the parts around plunger barrel II, notch I03 when positioned opposite the plunger mechanism, permits ready passage of spring 4|, retainer plate 43 and associated parts. positioned after removal of stop pin I01.

To urge gear member 11 to the previously mentioned predetermined fixed position, I preferably provide a coil spring I08 about hub 84 of gear member 11 and in the space between gear side 36 and extension wall 00. The spring is connected at one end to a pin I09 fixed in gear member 11, and at the opposite end to a pin III fixed in pump casing 2. In addition to urging pump gearing 1I and 11 to a predetermined position, spring I08 is desirable because it takes out backlash in the system, which makes for more accurate metering of fuel; and also should the governor spring or control linkage break, then in a plurality of pumps in an engine, springs I03 will always turn all the pump plungers to shut-oil position, stopping the engine.

In the event the governor control mechanism Such notch I03 may be thus is disconnected from rack bar 4, opening I! of coupling member 00 will not necessarily be fixed at the no-load position thereof, but might be at any intermediate position. Also should gear 11 be manually turned, while the pump is removed from the engine, and should spring I03 fail to return it to a predetermined fixed position, it too might accidentally be at any intermediate position. Therefore, as an added precaution to insure proper mating of coupling elements 33 and II", and assembly of gear 11 in relation to coupling member 33, should either be in an intermediate position, I provide the previously mentioned wing extensions I00, on coupling member 00, which interfere with pin IOI unless the gear 11 and coupling member 06 are in proper position for correct timing of the pump.

In my preferred pump construction, I preferably employ special means to bleed air away from the pump. This is of particular advantage in a radial engine where some pumps may be located upside down. With'reference to Fig. 1, it will be noted that fuel is supplied to fuel inlet port 22, through fuel inlet passage I it having a lateral extension II1 leading directly to port 22. Fuel inlet passage IIG communicates with a similar passage 0' in control casing 3; suitable sealing structures II3 being provided between the fuel passages in the pump casing and in the control casing. As is customary in the art, fuel is supplied to fuel inlet passage II6 by means of.a transfer pump (not shown) which feeds fuel at a relatively low pressure of about fifteen to twenty (15-20) pounds per square inch. Communicating with fuel inlet extension passage H1 and adjacent inlet port 22, is a fuel return passage II9 which leads fuel back to the source of supply at atmospheric or zero gage pressure; fuel return passage II3 communicating with a similar passage II! in control casing "3.

A tube or ferrule member I23 is mounted in inlet extension II1 between the main inlet p'assage II6 and inlet port 22, and has an end I24 adjacent port 22 which is of less outside diameter than the inside diameter of inlet extension turn passage II3; tube I23 having a peripheral groove I21 in line with return passage II9, to permit free flow of fuel into the return passage.

As fuel is pumpedthrough inlet passage Ill and through tube I23, a portion thereof will by-pass back through restricted orifice I26 and into return passage II9 but at a much higher velocity by virtue of the'restriction offered by orifice I26. This creates a more favorable path for flow of air than through inlet port 22. Consequently, air will be bled away from the pump with the result that air binding is avoided. ,By virtue of the fact that an annular-like restricted orifice is provided, it will be noted thatirrespective of the location of the pump, namely, whether it is right side up or upside down, there will always be a restricted portion in an upright position through which air, which always rises, will flow. Therefore, the described arrangement functions properly irrespective of the position of the pump.

I claim 1. Fuel injection mechanism comprising housing means, a pump plunger mounted for reciprocation in the housing means to feed fuel under pressure and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, tappet mechanism adjacent an end of the plunger for moving the plunger axially in the plunger shoulder, spring means between the retainer member and an abutment in the housing means for moving the plunger in an opposite direction, the sleeve having an opening in the periphery thereof, a gear member secured to the plunger within the sleeve between said sleeve wail and said plunger shoulder and having its teeth accessible through the sleeve opening, another.

gear member engaging the first mentioned gear member and which is journalled in the housing means, stop means within the housing means for limiting the extent of turning of the second mentioned gear member, and spring means between the housing means, and said second mentioned gear member for urging such gear member toward a predetermined position against the stop means.

2. Fuel injection mechanism comprising housing means having an internal shoulder, a check valve cage adjacent said shoulder, a pump cylinder remova-biy mounted within said housing means having an enlarged head portion at one end thereof adjacent the cage, a nut screwed within the housing means applying pressure against the head to clamp the valve cage and the pump cylinder between it and the shoulder, a-

pump plunger mounted for reciprocation in the pum cylinder to feed fuel under pressure and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, an endportion of the plunger extending beyond an end of the sleeve, tappet mechanism adjacent said end portion of the plunger for moving the plunger axially in one direction, a guide sleeve slidably mounted in the housing means into which the tappet end portion of the plunger projects, a spring retainer member about the plunger adjacent the sleeve, spring means between the retainer member and an abutment in the housing mean for moving the plunger in an opposite direction, the sleeve having an opening in the periphery thereof, a gear member secured to the plunger within the sleeve having its teeth acces sible through the sleeve opening, another gear member engaging the first mentioned gear memher and which is journalled in the housing means, stop means within the housing means for limiting the extent of turning of the second mentioned gear member, spring means between the housing means and said second mentioned gear member for urging such gear member toward a predetermined position against the stop means, and means including a rod detachably engaged with said second mentioned gear member for turning the second mentioned gear member to effect angular adjustment of the plunger.

3. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, a pump control casing to which the pump casing i adapted to be detach-ably connected, gearing in the pump casing for enabling angular adjustment of the pump plunger upon movement of said gearing, means detachably connectable to said gearing and supported by the control casing for moving said gearing, and means for retaining said gearing in a predetermined position for connection with the moving means in the control casing.

4. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering or fuel is controlled by angular adjustment of the plunger, 9. pump control casing to which the pump casing is adapted to be detachably connected, gearing in the pump casing for enabling angular adjustment oi the pump plunger upon movement 01' said gearing, governor "controllable means detachably connectable to said gearing and supported by the controlcasing for moving said gearing, and stop means supported by the pump casing for positioning said gearing in a predetermined phase position when it is detached from said governor controllable means.

5. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, 9. pump control casing to which the pump casing is adapted to be detachably connected, gearing in the pump casing for enabling angular adjustment of the pump plunger upon movement of said gearing, one of the gear members of said gearing being connected to the plunger and a second of such gear members being supported by the pump casing, means supported by the control casing for moving said gearing including a turnable member, means enabling detachable connec'tion'at a predetermined position between said turnable member and said second gear member, and means supported by the pump casing for urging said gear member to assume said predetermined 'position.

6. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, 9. pump control casing to which the pump casing is adaptedto be detachably connected, gearing in the pump casing for enabling angular adjustment of the pump plunger upon movement of said gearing, one of the gear members of said gearing being connected to the plunger and a second of such gear members being supported by the pump casing, means supported by the control casing for moving said gearing including a turntable member, means enabling detachable connection at a predetermined position between said turnable member and said second gear member including a pin on one ofsaid members adapted to engage another of such members which has an opening therein for receiving said pin, and resilient means supported by the pump casing for urging said second gear member toward said predetermined position.

7. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which isof the type wherein metering of fuel is controlled by angular adjustment of the plunger, a pump control spaced from a wall of the pump casing, means supported by the control casing for moving said gearing including a turnable member, means en abling detachable connection at a predetermined position between said turnable member and said second gear member, stop means within the pump casing for limiting the extent of turnin of the second gear member. and a coil spring in the space between said side of the second gear member and said pump casing wall and connected between the pump casing and said second gear member for urging such gear member toward said predetermined position against said stop means.

8. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, gearing in the casing for enabling angular adjustment of the pump plunger upon movement of said gearing, one ofthe gear members of said gearing being connected to the plunger and a second of such gear members being supported by the easing, said second gear member having a side spaced from a wall of the casing, stop means within the casing for-limiting the extent of turning of the second gear member, and a coil spring in the space between said side of the second gear member and said pump casing wall and connected between the pump casing and said second gear member for urging such' gear member toward a predetermined position against said stop means.

9. Fuel injection pump mechanism comprising a pump casing containing a pump plunger mounted for reciprocation and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, apump control casing to which the pump casing is adapted to be detachably connected, movable means in the pump casing enabling angular adjustment of the pump plunger including a turnable member, means in the control casing for moving said movable means including another turnable member, coupling elements on said turnable members enabling detachable connection between said turnable members at a predetermined position thereof, and means for retaining said members in position for proper mating of 'said coupling elements when they are detached.

1G. Fuel injection mechanism comprising housing means, a pump plunger mounted for reciprocation in the housing means to feed fuel under pressure and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, the plunger being adapted to be moved axially in one direction by tappet mechanism adjacent an end of the plunger, a guide sleeve slidablymounted in the housing means into which the tappet end portion of the plunger projects, a spring retainer member mounted on the plunger above the guide sleeve, the spring retainer member contacting the top of the guide sleeve in the downward movement of the plunger to stop and limit the downward movement of the plunger by the spring, spring means between the retainer member and an abutment in the housing means for movin the plunger in an opposite direction, the sleeve having an opening in the periphery thereof, and'a toothed member secured to the plunger within the sleeve and having its teeth accessible through the sleeve opening to enable the plunger to be angularl adjusted.

11. Fuel injection mechanism comprising hous-' riphery thereof, and a ing means, a pumpplunger mounted for reciprocation in the housin means to feed fuel under pressure and which is'of the type wherein metering of fuel is controlled by angular adjustment of the plunger, tappet mechanism adjacent an end of the plunger for moving the plunger axially in one direction, a guide sleeve slidably mounted in the housing means into which the tappet end portion of the plunger projects and having a-wall between the tappet end of the plunger and the tappet mechanism, a shoulder on the plunger adjacent an end of the sleeve and spaced from said sleeve wall, a spring retainer member about the plunger adjacent said end of the sleeve and the plunger shoulder, spring means between the retainer member and an abutment in the housing means for moving the plunger in an opposite direction, the spring retainer member contacting the top of the guide sleeve in the downward movement of the plunger to stop and limit the downward movement of the plunger by the spring, the sleeve having an opening in the petoothed member secured to the plunger within the sleeve between said sleeve wall and said plunger shoulder and having its teeth accessible through the sleeve opening to enable the plunger to be angularlyadjusted,

12. Fuel injection mechanism comprising housing means, a, pump plunger mounted for reciprocation in the housing means to feed fuel under pressure and which is of the type wherein metering of fuel is controlled by angular adjustment of the plunger, tappet mechanism adjacent an end of the plunger for moving the plunger axially in one direction, a guide sleeve slidably mounted in the housing means intov which the tappet end portion of the plunger projects and having a wall between the tappet end of the plunger and the tappet mechanism, a shoulder on the plunger adjacent an end of the sleeve and spaced from said sleeve wall, a spring retainer member about the plunger adjacent said end of the sleeve and the plunger shoulder, spring means between the retainer member and an abutment in the housing means for moving the plunger in an opposite direction, the spring retainer member contacting the top of the guide sleeve in the downward movement of the plunger to stop and limit the downward movement of the plunger by the spring, the

' sleeve havin an opening in the periphery'thereof,

a gear member secured to the plunger within the sleeve between said sleeve wall and said plunger shoulder and having its teeth accessible through the sleeve opening, and means for turning the gear member to angularly adjust the plunger including another gear member engaging the first mentioned gear member and which is journalled in the housing means.

13. Fuel injection mechanism comprising hous ing means having an internal shoulder, a check valve cage removably mounted within the housing and adjacent the shoulder having a check valve therein, a pump cylinder removably mounted Within the housing means having an enlarged head portion at one end thereof forming a retainingmeans to hold the valve cage in place within the housing and a nut about the cylinder screwed within the housing means applying pressure against said pump cylinder head to clamp the cage and the pump cylinder between it and the shoulder.

14,. Fuel injection pump mechanism comprising a, pump casing and a pump control casing separably connected, means contained by the pump casing for metering the pump capacity,

1 tion corresponding to means contained by the control casing and operably connected with the metering means when the casings are connected for actuating the metering means, and means normally holding the metering means in phase position for connection with its actuating means when the casings are brought together for connection.

15. Fueliniection pump mechanism comprising a pump casing and a pump control casing separably connected, means controlled by the pump casing for metering the pump capacity, governor operated means contained by the control casing and operably connected with the meterlng means when the casings are connected for actuating the metering means, and means normally holding the metering means in phase posithe static position of the governor to facilitate assembly 01 the casings to their connected positions.

16. Fuel injection pump mechanism comprising a pump casing and a pump control casing separably connected, fuel metering means for the pump including a pump adjusting gear carried REFERENCES CITED The following references are of record in the flie of this patent:

NITED STATES PATENTS Number Name Date 1,845,600 Herr Feb. 16, 1932 1,854,009 Wilkinson Apr. 12, 1932 1,951,215 Sidney Mar. 13, 1934 1,967,101 Rassbach et al July 17, 1934 2,097,413 Hurst et al Oct. 26, 1937 2,127,211 Edwards Aug. 18, 1938 2,223,756 Dillstrom Dec. 3, 1940 2,296,357 Links et al. Sept. 22, 1942 

